Whenever martin has a restaurant bill with an amount between \(\$10\) and \(\$99,\) he calculates the dollar amount of

[Gmat_mission]

Whenever martin has a restaurant bill with an amount between \(\$10\) and \(\$99,\) he calculates the dollar amount of the tip as \(2\) times the tens digit of the amount of his bill. If the amount of Martin's most recent restaurant bill was between \(\$10\) and \(\$99,\) was the tip calculated by the martin on this bill greater than \(15\) percent of the amount of the bill?

(1) The amount of the bill was between \(\$15\) and \(\$50.\)
(2) The tip calculated by the martin was \(\$8.\)

Answer: B

Source: Official Guide

[deloitte247]

If $10 < bill < $99 and tip is 2 * tens digit of bill
Target question: Was the tip calculated by the martin on this bill greater than 15% percent of the amount of the bill?

Statement 1: The amount of the bill was between $15 and $50
$15 < bill < $50
If bill is $16, then tips = 2 * 1 = 2
15% of bill = 15% * 16 = 2.4
So, the tip was less than 15% of the bill.
But if bill is $32, then tips = 2 * 3 = 6
15% of bill = 15% * 32 = 4.8. So, tip is greater than 15% of the bill. Therefore, the information available does not provide a definite answer. Hence, statement 1 is NOT SUFFICIENT.

Statement 2: The tip calculated by the martin was $8
$$This\ means\ that\ 40\le Bill\le49$$
The minimum possible value of the bill is $40 and the maximum is $49.
So, if the bill is $40, 15% of bill = 15% * 40 = 6
So, if the bill is $49, 15% of bill = 15% * 49 = 7.35
In all the possible values of the bill, the tip is greater than 15% of the bill. Therefore, statement 2 is SUFFICIENT.

Hence, the correct answer is option B.